1. ABSTRACT Maternal mortality in the United States is higher than any other developed country and non-Hispanic black women are dying at 2.5 times the rate of non-Hispanic white women, and 3.1 times the rate of Hispanic women. Methodological differences between studies investigating the timing and etiology of maternal mortality vary, but studies including self-harm and extending to the full year postpartum demonstrate that drug overdose and suicide combined are the leading cause of maternal mortality. While rates of detection and treatment of Substance Use Disorder (SUDs) and Mental Health Disorders (MHD) during pregnancy and the year postpartum [i.e., peripartum period] are low for all women, there are clear racial inequities that need to be addressed as part of an overall strategy to reduce maternal mortality and create health equity. With the support of the National Institute on Drug Abuse (NIDA) parent award (R34 DA04673) we developed Listening to Women (LTW); a mobile phone-based program designed to improve peripartum SUD and MHD screening, and treatment as well as enhance communication between women, obstetric and addiction/psychiatric providers during pregnancy and throughout the postpartum year. Preliminary data demonstrate significant improvements in Screening, Brief Intervention, and Referral to Treatment (SBIRT) with LTW, compared to in-person SBIRT. We also identified racial disparities with in-person SBIRT, which were not present with LTW. The long-term goal of this proposal is to inform the development of an effective, patient-informed intervention to reduce racial disparities and morbidity and mortality associated with untreated peripartum SUDs and MHDs. The objectives of the current application are to work with community partners, peer-led SUD and MHD recovery organizations and peripartum black women to: 1) better understand barriers to identifying, and treating peripartum SUDs and MHDs; and 2) modify LTW based on this feedback. This research will result in a critical advance in the development of a program to reduce racial disparities and maternal mortality due to untreated peripartum SUDs and MHDs as well as enhance communication and coordination of care between healthcare providers. In addition, this study will generate preliminary data necessary for further efficacy testing of the LTW program.